METHOD FOR MANUFACTURING ELECTROMECHANICAL CONVERSION ELEMENT, ELECTROMECHANICAL CONVERSION ELEMENT, DROPLET DISCHARGE HEAD, DROPLET DISCHARGE DEVICE AND IMAGING APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing an electromechanical conversion element, by which a decrease in a quantity of deformation (i.e. a quantity of surface displacement) with a voltage applied to a piezoelectric film after having repeated the application of a predetermined drive pulse signal 3.6×10times in the case of the piezoelectric film including PZT can be suppressed to 97% or more of that before repeating the application of the drive pulse signal.SOLUTION: In a method for manufacturing an electromechanical conversion element having a piezoelectric film including PZT, the expressions (1) and (2) are satisfied: -Ec-(-Ec)<0 (1); and |-Ec-(-Ec)|>0.15×Ec(2), where -Ec is an initial negative polarity-side coercive electric field of the electromechanical conversion element, -Ecand Ecrespectively represent a coercive electric field on a negative polarity side, and a coercive electric field on a positive polarity side after execution of a polarization process including the step of applying a voltage on the positive polarity side, and the average value of respective absolute values of the coercive electric fields -Ecand Ecis given by Ec(=(|-Ec|+Ec)/2).